Microsoft .NET Core (April 2026)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the Microsoft Security Updates API. The text
# itself is copyright (C) Microsoft Corporation.
#
##

include('compat.inc');

if (description)
{
  script_id(307353);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/08");

  script_cve_id(
    "CVE-2026-26171",
    "CVE-2026-32178",
    "CVE-2026-32203",
    "CVE-2026-33116"
  );
  script_xref(name:"IAVA", value:"2026-A-0339");
  script_xref(name:"MSKB", value:"5086095");
  script_xref(name:"MSKB", value:"5086096");
  script_xref(name:"MSKB", value:"5086097");
  script_xref(name:"MSFT", value:"MS26-5086095");
  script_xref(name:"MSFT", value:"MS26-5086096");
  script_xref(name:"MSFT", value:"MS26-5086097");

  script_name(english:"Microsoft .NET Core (April 2026)");

  script_set_attribute(attribute:"synopsis", value:
"The Microsoft .NET Core installations on the remote host are affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The Microsoft .NET Core installations on the remote host are missing
security updates. It is, therefore, affected by multiple
vulnerabilities:

  - Denial of Service (CVE-2026-26171, CVE-2026-32203,
CVE-2026-33116)

  - Improper neutralization of special elements in .NET allows an
unauthorized attacker to perform spoofing over a network. (CVE-2026-32178)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://github.com/dotnet/core/blob/main/release-notes/8.0/8.0.26/8.0.26.md
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?117fa405");
  # https://github.com/dotnet/core/blob/main/release-notes/9.0/9.0.15/9.0.15.md
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8f0a740c");
  # https://github.com/dotnet/core/blob/main/release-notes/10.0/10.0.6/10.0.6.md
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?94ea4382");
  script_set_attribute(attribute:"see_also", value:"https://github.com/dotnet/core/issues/10356");
  script_set_attribute(attribute:"solution", value:
"Update to .NET Core 8.0.26, 9.0.15, 10.0.6, or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-32178");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2026-33116");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/04/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:.net_core");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("microsoft_dotnet_core_win.nbin");
  script_require_keys("installed_sw/.NET Core Windows");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'requires': [{'scope': 'target', 'match': {'os': 'windows'}}],
  'checks': [{
    'product': {'name': '.NET Core Windows', 'type': 'app'},
    'check_algorithm': 'default',
    'constraints': [{
      'min_version': '8',
      'fixed_version': '8.0.26'
    },{
      'min_version': '9',
      'fixed_version': '9.0.15'
    },{
      'min_version': '10',
      'fixed_version': '10.0.6'
    }]
  }]
};

var result = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_HOLE);
vdf::handle_check_and_report_errors(vdf_result:result);